Aggressive behaviors are common among youth with autism spectrum disorder (ASD) and correlate with pervasive social-emotional difficulties. Communication skill is an important correlate of disruptive behavior in typical development, and clarification of links between communication and aggression in ASD may inform intervention methods. We…

This study examined sex differences in externalizing and internalizing symptoms of children with ASD without intellectual disability (ID). The sample (n = 80) included 40 girls and 40 boys, ages 6-12 years, with ASD (without ID) matched on age and IQ. Externalizing and internalizing symptoms were significantly elevated for this sample (girls and…

Self-injurious behavior (SIB) occurs in up to 50% of individuals with autism. As one of the most serious conditions in individuals with developmental disabilities, SIB affects the individual and his or her family in multiple contexts. A systematic analysis of factors most commonly associated with SIB could inform the development of individualized…

Using a dataset involving 415 individuals with irritability, aggression, agitation and self-injury (IAAS) behaviors from the fragile X syndrome (FXS) FORWARD database, we describe the psychopharmacologic management of IAAS and features of the population of persons with FXS treated with drug therapy for IAAS. Among those with FXS exhibiting IAAS,…

Background: Adults with intellectual disabilities (ID) commonly live in specialised residential settings. Data collected from these adults are often nested. The aim of this study is to examine the impact of this data structure. Method: Referent caregivers completed the Reiss Screen for Maladaptive Behaviour for each of the 571 adults with ID who…

Aggressive behaviors in those with intellectual disability (ID) and autism (ASD) have been linked to a variety of factors including ID level, age, sex, psychiatric disorders, and medical conditions but these factors have not been studied, in large samples, in terms of how they affect the stimuli that trigger aggression. In this survey of 2243…

Previous research is not conclusive in detailing the prevalence of challenging behaviour and its correlates in children with intellectual disabilities in school settings in particular. In the current study, an amended version of the Behaviour Problems Inventory -- Short Form was used to collect data from a sample of 321 students in a special…

This mixed-methods study examined gender differences in the social motivation and friendship experiences of adolescent boys and girls with autism relative to those without autism, all educated within special education settings. Autistic girls showed similar social motivation and friendship quality to non-autistic girls, while autistic boys…

Twenty-seven boys and eight girls with ASD and thirty-five controls matched for gender, age and total score intelligence were studied to ascertain whether boys and girls with ASD display stronger reactive aggression than boys and girls without ASD. Participants performed a computerized version of the Pulkkinen aggression machine that examines the…

A gap exists in the literature regarding aggression in autism spectrum disorders and how this behavior compares to other groups. In this multisite study, the "Children's Scale for Hostility and Aggression: Reactive/Proactive" and the Aggression subscale of the "Child Behavior Checklist" were rated for 414 children with autism…

This study compared sibling adjustment and relationships in siblings of children with Autism Spectrum Disorder (ASD-Sibs; n = 69) and siblings of children with typical development (TD-Sibs; n = 93). ASD-Sibs and TD-Sibs demonstrated similar emotional/behavioral adjustment. Older male ASD-Sibs were at increased risk for difficulties. Sibling…

Anger related behaviours such as aggression are known to be an area of difficulty for children with autism spectrum disorders (ASD). A national internet forum for parents of children with ASD was selected out of other similar forums from six English speaking countries. Information about the angry episodes of 121 children with ASD as described by…

Background: Previous evidence has suggested that clinical characteristics may predict use of restraint in adults with intellectual disability. However, the relationship between specific types of untoward incidents, corresponding interventions (restrictive procedures) and clinical psychopathology remains unclear. Method: We examined all untoward…

Background: This study investigates the role of IQ, autistic traits and challenging behaviours in affecting adult outcomes among adolescents who receive special educational assistance. Methods: A total of 58 participants were recruited from an ongoing longitudinal study. All received assessments of IQ, behavioural patterns (using the Childhood…

Background: The link between aggression and mental disorders has been the focus of diverse studies in persons with and without intellectual disabilities (ID). Because of discrepancies in the finding of studies in persons with ID to date, and because of differences in research design, instruments used and the population studied, more research is…